I have recently got a slow down with this BQM.
Restarted router, changed cabling. Restarted ONT. No improvement. With Zen 900/100.
My gut instinct is you should check your router's configuration to make sure it's not rate limiting the pings. I've checked the route to you specifically and I don't see anything until the last hop although there isn't a response from the few hops before so I can't bet sure. The sawtooth pattern makes me think your router might be rate limiting it potentially and then removing, then adding, etc..
That is very bad packet-loss. I would probably suggest you measure ping times on the command line and see what the pattern looks like. You're likely to see 10-30% packet-loss based on that graph (except when it goes low again like at 1am and at the end of the graph just before midnight).. do this for the following:
212.23.8.1 - this is one of Zen's name servers
80.249.99.164 - this is the box that does the pinging
8.8.8.8 - this is google's name server
212.58.249.144 - this is a BBC server
On Mac/Linux: ping -i .2 212.23.8.1
On Windows drop the -I but you will only see one ping per second which won't show you the issue as well so run for a few minutes
If you measure it outbound then it's not going to be your router responding but the server on the other end. If you see heavy packet loss then it's probably a router or Zen issue.. if you don't, then your router might just be filtering ICMP traffic heavily. When I ping your IP I get this:
64 bytes from x.x.x.x: icmp_seq=13 ttl=58 time=9.89 ms
64 bytes from x.x.x.x: icmp_seq=18 ttl=58 time=9.86 ms
64 bytes from x.x.x.x: icmp_seq=23 ttl=58 time=9.39 ms
64 bytes from x.x.x.x: icmp_seq=27 ttl=58 time=9.60 ms
64 bytes from x.x.x.x: icmp_seq=32 ttl=58 time=9.30 ms
As you can see from the sequence numbers, it's losing a lot of packets in between.. that's on a one second interval. Windows ping won't show you the sequence numbers but you will see a packet dropped I think.
If this was a link congestion situation, you'd see latency spikes but latency is perfectly ok.. i.e. either a packet is responded to or it's not.. if it is then the performance is fine.. this makes me think the router is doing something - you may have a denial of service protection mode enabled or such. Can you let us know here as it would be a good example to add to our FAQ if so
seb